Engine Does Not AutoStop: Autostop/Autostart
WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
The Two-Mode Hybrid vehicle does not require internal combustion engine operation at all times. After a successful engine start, the hybrid powertrain control module may turn off the engine, or Autostop, when not required for the current vehicle conditions. The engine will remain off while in Autostop mode, until such time that vehicle conditions require the engine to run. The near-instant starting of the engine from Autostop mode is called Autostart.